| 초록 |
Colloidal quantum dots (CQDs) based photodetectors were developed and their performance was improved by introduction of cathode buffer layer (CBL) on to the ZnO surface. Polyethylene imine ethoxylated (PEIE) and polyethylene glycol (PEG) were selected as CBL, which enhanced the interfacial contact between CQDs and ZnO layers. The dark current of the photodetectors was dramatically decreased by the improved interfacial contact property and the photocurrent is increased by decreased work function of ZnO/CBLs due to forming a permanent dipole moment at the interfaces of ZnO and CBLs. As a result, we could effectively increase the on-off ratio, responsivity and detectivity of the photodetectors. |
